Answers

more likely these planets are so far away, by the time we could get there, we would just find a dormant planet, or a place that we would not find life as we knew it cause, our brain could not adjust to magnetic signals on that planet.

That *is* possible, and has been proposed... And terribly sad if that's true. I would hazard a guess that not all civilizations are the same - and I'm hoping at least a *few* progress to the point of peace between themselves.
And, I would say we have a ways to go - but I'm hopeful for our civilization as well.

The premier reason we see no signs of alien civilizations is that they do not exist within thousands of light years of us, which is as far as our powers of detection reach. They don't exist because they never did exist.

We can fantasize possibilities beyond count, but consider, IF such extraterrestrial intelligence even exist,, they are so far distant we would never know of their existence, nor them of ours.
Just because humans will bring about their own extinction, you can't typecast all civilizations as doing the same.
The word civilization comes from the word civilized, a grouping of animals living together in harmony.
A barbaric civilization is an oxymoron.

That was, roughly, Carl Sagan's theory.
Considering Drake's equation
N = R * fp * ne * fl * fi * fc * L
And using his own hypothesis for R, fp, ne, fl, fi and fc, Sagan deduced than L must be very short, since, else, we would have made contact more easily with another civilisation.

Sagan from there deduced that civilisations have a tendency to destroy themselves. And therefore that we should anticipate the same fate to avoid it. That was the reason why he became so worried about environment and atomic weapons.

That is one part of the Drake equation and also part of the theory of civilization technology levels (Kardashev scale) and the bottleneck hypothesis. The bottleneck hypothesis says that advancing to type 2 or type 3 involves a very high risk of technological self-destruction, so only the very rare system can make it through without self-destruction, and thus it is not solely because it is hard to get that advanced, but that it is hard to get that advanced and not fall off in the process.